During the previous year, the major emphasis of our work with hepatotrophic factors was upon acute regeneration, upon how portal flow or the lack of it influences this process, and how insulinoprival states deviate the process. During the coming year, attention will be focused upon replacement experiments. After performing totally diverting portacaval shunts, the stump of the portal vein at the liver hilum will be cannulated and infused for several days with pancreatic hormones. Highly purified insulin, glucagon, and an insulin-glucagon mix in a physiologic molar ratio will be tested. These experiments should define the optimal hormonal concentrations for hepatic protection from the injury of portal diversion. BIBLIOGRAPHIC REFERENCES: Putnam, C. W. and Starzl, T. E.: Complications of transplantation. In Complications of Surgery and Their Management, Third Edition (Artz, C.P. and Hardy, J. D., Eds.). Philadelphia, W. B. Saunders, Co., 1975, pp. 741-782. Starzl, T. E., Putnam, C. W. and Corman, J. L.: Transplantation of the liver. In Diseases of the Liver, 4th Edition (Schiff, L., Ed.). Philadelphia, J. B. Lippincott Company, 1975, pp. 1147-1172.